Wednesday, February 10, 2010

Sharks and Virgin Births

Brian Worley, who runs the entertaining ‘lapsed Christian’ site (I hope that is not an impolite way to describe it) called exminister, has asked if I might comment on a story about ‘virgin births’ in sharks. Brian wondered whether there was a possibility that Christians might be prompted by this report to say ‘look, virgin births are a proven scientific fact…’. It would be a very unwise Christian who did so, since this sort of asexual parthenogenetic reproduction has been known for a very long time in a variety of creatures, including vertebrates such as lizards and fish (it’s not even a new discovery in sharks). To say that it must therefore be possible in humans would be much the same as to say that humans might grow a new limb after amputation, or that they might lay eggs or breathe underwater. Now, far be it for me to underestimate people’s capacity to say some peculiar things, but I think even the most committed fundamentalist might have to admit this one is a bit of a non-starter.

Besides, if anyone did want to use parthenogenesis as a scientific defence of the Virgin Birth, they would also then have to deal with the tricky issue that it would make Jesus a clone of Mary, not to mention the treacherous theology of the nature of Jesus’s flesh and embryogenesis.

All the same, Brian is by no means out on a limb here. When parthenogenesis was first induced artificially, and thus proven as scientific fact, the Virgin Birth was most certainly invoked. This happened in the 1890s, through the work of the German biologist Jacques Loeb at the research centre for marine biology in Woods Hole, Massachusetts. He caused an unfertilized sea-urchin egg to divide by treating it with a mixture of simple salts such as sodium chloride and magnesium chloride – in essence, with a kind of reformulated sea water. In organisms that reproduce sexually, the development of an egg into a new organism generally proceeds only when it has united its genetic material with that of a spermatozoa. But Loeb’s discovery revealed that in some species this was strictly optional. It is not the provision of genes that constitutes the sperm’s role in triggering growth of an embryo, but some other function – one that can be carried out by other means. When an egg is thus provoked to commence parthenogenesis, the resulting organism is thus, as I say, a clone of the egg’s parent organism, with identical genetic constitution. Loeb had not so much created life as invented cloning.

In 1899, the Boston Herald reported on this work with the headline ‘Creation of Life. Startling Discovery of Prof. Loeb. Lower Animals Produced by Chemical Means. Process May Apply to Human Species. Immaculate Conception Explained.’ That might sound like hysterical over-extrapolation of the sort that makes scientists roll their eyes in despair. But in this case it seems fair enough, for look at what Loeb had written in his account of the discovery:
“The development of the unfertilized egg, that is an assured fact. I believe an immaculate conception may be a natural result of unusual but natural causes. The less a scientist says about that now the better. It is a wonderful subject, and in many ways an awful one. That the human species may be made artificially to reproduce itself by the withdrawal of chemical restraint by other than natural means is a matter we do not like to contemplate. But we have drawn a great step nearer to the chemical theory of life and may already see ahead of us the day when a scientist, experimenting with chemicals in a test tube, may see them unite and form a substance which shall live and move and reproduce itself.”

Loeb’s discovery was no chance affair. He had been experimenting for some years on the control and manipulation of sea-urchin development using salts, at first under the instruction of the American biologist Thomas Hunt Morgan (whose supporters later accused Loeb of stealing his ideas) at Bryn Mawr College in Pennsylvania. But the breakthrough put Loeb in the limelight, a position that he seemed rather to enjoy. Despite early scepticism, his work was widely lauded, and in 1901 he narrowly missed out on being awarded a Nobel prize.

The work was soon followed up by others, and in 1910 the French scientist Eugene Battaillon in Dijon discovered that frog eggs could be induced to start developing into embryos by being pricked with a needle. The embryologist Frank Rattray Lillie, then at the University of Chicago and later founder of the Woods Hole Oceanographic Institution, was particularly interested in whether the trick would work for humans, and hinted that this should be possible. (It is not, apparently – human development differs in some important ways from that of sea urchins and frogs.)

Loeb and other biologists viewed the prospect of human parthenogenesis triggered by salt with somewhat uneasy humour, joking that ‘maiden ladies’ might feel compelled to stop bathing in the sea. More telling was the notion that Loeb had revealed males to be redundant. He apparently received letters from women asking him to induce artificial parthenogenesis in their own ova, while the French embryologist Yves Delage, who worked on the problem, was sent letters congratulating him from freeing women from ‘the shameful bondage of needing a man to become a mother.’ These are prescient themes: artificial means of conceiving a baby, however hypothetical, are now seen both as removing women’s control of their own reproductive destiny (and placing it under the favour of male scientists) and as liberating them to take control unilaterally. Equally telling as a taste of what was to come, another report speculated about the possibility of raising ‘domestic animals and children born without help of a male through an operation which would be regulated scientifically and almost commercially, similar to raising the fry of trout.’ Aldous Huxley waits in the wings.

If you want to know more about this stuff, you’ll be able to get it in my next book Unnatural: The History of the Heretical Idea of Making People, which will be published by Bodley Head some time next year.

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